Pen



FIG. 1 is a front elevational view of a pen showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a left side elevational view thereof, without the cap, theright side view being a mirror image thereof;

FIG. 5 is a left side elevational view of the cap, the right side viewbeing a mirror image thereof; and

FIG. 6 is a front elevational view of a pen showing my new designwithout the cap.

The ornamental design for a pen, as shown and described.